[PATCH] D90316: [FPEnv] Diagnose pragmas FENV_ROUND,_ACCESS and float_control if target does not support StrictFP

[Melanie Blower via Phabricator via cfe-commits]

This revision was landed with ongoing or failed builds.
This revision was automatically updated to reflect the committed changes.
mibintc marked an inline comment as done.
Closed by commit rG13bfd89c4962: [clang][FPEnv] Diagnose Strict FP pragmas if 
target does not support StrictFP (authored by mibintc).

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Files:
  clang/include/clang/Basic/DiagnosticParseKinds.td
  clang/lib/Parse/ParsePragma.cpp
  clang/test/Parser/pragma-fp-warn.c


Index: clang/test/Parser/pragma-fp-warn.c
===
--- /dev/null
+++ clang/test/Parser/pragma-fp-warn.c
@@ -0,0 +1,19 @@
+
+// RUN: %clang_cc1 -triple wasm32 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple thumbv7 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple aarch64 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple x86_64 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple systemz -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple powerpc -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+#ifdef EXPOK
+// expected-no-diagnostics
+#else
+// expected-warning@+4 {{'#pragma float_control' is not supported on this 
target - ignored}}
+// expected-warning@+5 {{'#pragma FENV_ACCESS' is not supported on this target 
- ignored}}
+// expected-warning@+6 {{'#pragma FENV_ROUND' is not supported on this target 
- ignored}}
+#endif
+#pragma float_control(precise, on)
+
+#pragma STDC FENV_ACCESS OFF
+
+#pragma STDC FENV_ROUND FE_DOWNWARD
Index: clang/lib/Parse/ParsePragma.cpp
===
--- clang/lib/Parse/ParsePragma.cpp
+++ clang/lib/Parse/ParsePragma.cpp
@@ -103,6 +103,12 @@
 
   void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer,
 Token &Tok) override {
+Token PragmaName = Tok;
+if (!PP.getTargetInfo().hasStrictFP() && !PP.getLangOpts().ExpStrictFP) {
+  PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+  << PragmaName.getIdentifierInfo()->getName();
+  return;
+}
 tok::OnOffSwitch OOS;
 if (PP.LexOnOffSwitch(OOS))
  return;
@@ -2553,6 +2559,12 @@
  Token &Tok) {
   Sema::PragmaMsStackAction Action = Sema::PSK_Set;
   SourceLocation FloatControlLoc = Tok.getLocation();
+  Token PragmaName = Tok;
+  if (!PP.getTargetInfo().hasStrictFP() && !PP.getLangOpts().ExpStrictFP) {
+PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+<< PragmaName.getIdentifierInfo()->getName();
+return;
+  }
   PP.Lex(Tok);
   if (Tok.isNot(tok::l_paren)) {
 PP.Diag(FloatControlLoc, diag::err_expected) << tok::l_paren;
@@ -2952,6 +2964,11 @@
 Token &Tok) {
   Token PragmaName = Tok;
   SmallVector TokenList;
+  if (!PP.getTargetInfo().hasStrictFP() && !PP.getLangOpts().ExpStrictFP) {
+PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+<< PragmaName.getIdentifierInfo()->getName();
+return;
+  }
 
   PP.Lex(Tok);
   if (Tok.isNot(tok::identifier)) {
Index: clang/include/clang/Basic/DiagnosticParseKinds.td
===
--- clang/include/clang/Basic/DiagnosticParseKinds.td
+++ clang/include/clang/Basic/DiagnosticParseKinds.td
@@ -1147,6 +1147,9 @@
 def warn_stdc_unknown_rounding_mode : Warning<
   "invalid or unsupported rounding mode in '#pragma STDC FENV_ROUND' - 
ignored">,
   InGroup;
+def warn_pragma_fp_ignored : Warning<
+  "'#pragma %0' is not supported on this target - ignored">,
+  InGroup;
 // - #pragma comment
 def err_pragma_comment_malformed : Error<
   "pragma comment requires parenthesized identifier and optional string">;


Index: clang/test/Parser/pragma-fp-warn.c
===
--- /dev/null
+++ clang/test/Parser/pragma-fp-warn.c
@@ -0,0 +1,19 @@
+
+// RUN: %clang_cc1 -triple wasm32 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple thumbv7 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple aarch64 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple x86_64 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple systemz -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple powerpc -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+#ifdef EXPOK
+// expected-no-diagnostics
+#else
+// expected-warning@+4 {{'#pragma float_control' is not supported 

[PATCH] D90316: [FPEnv] Diagnose pragmas FENV_ROUND,_ACCESS and float_control if target does not support StrictFP

[Serge Pavlov via Phabricator via cfe-commits]

sepavloff accepted this revision.
sepavloff added a comment.
This revision is now accepted and ready to land.

LGTM.




Comment at: clang/test/Parser/pragma-fp-warn.c:1
+
+// RUN: %clang_cc1 -triple wasm32 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s

I would propose to add a line with `-triple msp430`. This is a simple core, it 
is unlikely that it gets hardware FP support.


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[PATCH] D90316: [FPEnv] Diagnose pragmas FENV_ROUND,_ACCESS and float_control if target does not support StrictFP

[Melanie Blower via Phabricator via cfe-commits]

mibintc marked 2 inline comments as done.
mibintc added inline comments.



Comment at: clang/lib/Parse/ParsePragma.cpp:2967
+PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+<< PragmaName.getIdentifierInfo()->getName();
+return;

aaron.ballman wrote:
> Can you pass in `PragmaName` directly, or does that do unfortunate things 
> with single quotes?
After I changed it to PragmaName, the clang-format didn't find anything to fix


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[PATCH] D90316: [FPEnv] Diagnose pragmas FENV_ROUND,_ACCESS and float_control if target does not support StrictFP

[Melanie Blower via Phabricator via cfe-commits]

mibintc updated this revision to Diff 301708.
mibintc added a comment.

respond to @aaron.ballman 's review


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Files:
  clang/include/clang/Basic/DiagnosticParseKinds.td
  clang/lib/Parse/ParsePragma.cpp
  clang/test/Parser/pragma-fp-warn.c


Index: clang/test/Parser/pragma-fp-warn.c
===
--- /dev/null
+++ clang/test/Parser/pragma-fp-warn.c
@@ -0,0 +1,19 @@
+
+// RUN: %clang_cc1 -triple wasm32 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple thumbv7 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple aarch64 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple x86_64 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple systemz -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple powerpc -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+#ifdef EXPOK
+// expected-no-diagnostics
+#else
+// expected-warning@+4 {{'#pragma float_control' is not supported on this 
target - ignored}}
+// expected-warning@+5 {{'#pragma FENV_ACCESS' is not supported on this target 
- ignored}}
+// expected-warning@+6 {{'#pragma FENV_ROUND' is not supported on this target 
- ignored}}
+#endif
+#pragma float_control(precise, on)
+
+#pragma STDC FENV_ACCESS OFF
+
+#pragma STDC FENV_ROUND FE_DOWNWARD
Index: clang/lib/Parse/ParsePragma.cpp
===
--- clang/lib/Parse/ParsePragma.cpp
+++ clang/lib/Parse/ParsePragma.cpp
@@ -103,6 +103,12 @@
 
   void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer,
 Token &Tok) override {
+Token PragmaName = Tok;
+if (!PP.getTargetInfo().hasStrictFP() && !PP.getLangOpts().ExpStrictFP) {
+  PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+  << PragmaName.getIdentifierInfo()->getName();
+  return;
+}
 tok::OnOffSwitch OOS;
 if (PP.LexOnOffSwitch(OOS))
  return;
@@ -2553,6 +2559,12 @@
  Token &Tok) {
   Sema::PragmaMsStackAction Action = Sema::PSK_Set;
   SourceLocation FloatControlLoc = Tok.getLocation();
+  Token PragmaName = Tok;
+  if (!PP.getTargetInfo().hasStrictFP() && !PP.getLangOpts().ExpStrictFP) {
+PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+<< PragmaName.getIdentifierInfo()->getName();
+return;
+  }
   PP.Lex(Tok);
   if (Tok.isNot(tok::l_paren)) {
 PP.Diag(FloatControlLoc, diag::err_expected) << tok::l_paren;
@@ -2952,6 +2964,11 @@
 Token &Tok) {
   Token PragmaName = Tok;
   SmallVector TokenList;
+  if (!PP.getTargetInfo().hasStrictFP() && !PP.getLangOpts().ExpStrictFP) {
+PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+<< PragmaName.getIdentifierInfo()->getName();
+return;
+  }
 
   PP.Lex(Tok);
   if (Tok.isNot(tok::identifier)) {
Index: clang/include/clang/Basic/DiagnosticParseKinds.td
===
--- clang/include/clang/Basic/DiagnosticParseKinds.td
+++ clang/include/clang/Basic/DiagnosticParseKinds.td
@@ -1147,6 +1147,9 @@
 def warn_stdc_unknown_rounding_mode : Warning<
   "invalid or unsupported rounding mode in '#pragma STDC FENV_ROUND' - 
ignored">,
   InGroup;
+def warn_pragma_fp_ignored : Warning<
+  "'#pragma %0' is not supported on this target - ignored">,
+  InGroup;
 // - #pragma comment
 def err_pragma_comment_malformed : Error<
   "pragma comment requires parenthesized identifier and optional string">;


Index: clang/test/Parser/pragma-fp-warn.c
===
--- /dev/null
+++ clang/test/Parser/pragma-fp-warn.c
@@ -0,0 +1,19 @@
+
+// RUN: %clang_cc1 -triple wasm32 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple thumbv7 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple aarch64 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple x86_64 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple systemz -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple powerpc -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+#ifdef EXPOK
+// expected-no-diagnostics
+#else
+// expected-warning@+4 {{'#pragma float_control' is not supported on this target - ignored}}
+// expected-warning@+5 {{'#pragma FENV_ACCESS' is not supported on this target - ignored}}
+// expected-warning@+6 {{'#pragma FENV_ROUND' is not supported on this target 

[PATCH] D90316: [FPEnv] Diagnose pragmas FENV_ROUND,_ACCESS and float_control if target does not support StrictFP

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman added inline comments.



Comment at: clang/lib/Parse/ParsePragma.cpp:107
+if (!PP.getTargetInfo().hasStrictFP() && !PP.getLangOpts().ExpStrictFP) {
+  PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+  << "FENV_ACCESS";

Can you fix the lint issues (run the patch through clang-format)? Same for 
below.



Comment at: clang/lib/Parse/ParsePragma.cpp:2967
+PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+<< PragmaName.getIdentifierInfo()->getName();
+return;

Can you pass in `PragmaName` directly, or does that do unfortunate things with 
single quotes?



Comment at: clang/test/Parser/pragma-fp-warn.c:11-13
+// expected-warning@+8 {{'#pragma FENV_ROUND' is not supported on this target 
- ignored}}
+// expected-warning@+5 {{'#pragma FENV_ACCESS' is not supported on this target 
- ignored}}
+// expected-warning@+2 {{'#pragma float_control' is not supported on this 
target - ignored}}

I'd appreciate reversing the order of the comments so that they're in the same 
order as the pragmas below.


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[PATCH] D90316: [FPEnv] Diagnose pragmas FENV_ROUND,_ACCESS and float_control if target does not support StrictFP

[Melanie Blower via Phabricator via cfe-commits]

mibintc added a comment.

In D90316#2359366 , @kpn wrote:

> I also added "-fexperimental-strict-floating-point" which makes it possible 
> to write tests for a target when bringing up the support on that target. I 
> think it would be confusing for that flag to work on command line arguments 
> but not pragmas.

Thanks, I added this


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[PATCH] D90316: [FPEnv] Diagnose pragmas FENV_ROUND,_ACCESS and float_control if target does not support StrictFP

[Melanie Blower via Phabricator via cfe-commits]

mibintc updated this revision to Diff 301322.
mibintc added a comment.

Modified according to @kpn suggestion: if the command line has option 
fexperimental-strict-floating-point, the float pragmas will not be ignored.


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Files:
  clang/include/clang/Basic/DiagnosticParseKinds.td
  clang/lib/Parse/ParsePragma.cpp
  clang/test/Parser/pragma-fp-warn.c


Index: clang/test/Parser/pragma-fp-warn.c
===
--- /dev/null
+++ clang/test/Parser/pragma-fp-warn.c
@@ -0,0 +1,19 @@
+
+// RUN: %clang_cc1 -triple wasm32 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple thumbv7 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple aarch64 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple x86_64 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple systemz -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple powerpc -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+#ifdef EXPOK
+// expected-no-diagnostics
+#else
+// expected-warning@+8 {{'#pragma FENV_ROUND' is not supported on this target 
- ignored}}
+// expected-warning@+5 {{'#pragma FENV_ACCESS' is not supported on this target 
- ignored}}
+// expected-warning@+2 {{'#pragma float_control' is not supported on this 
target - ignored}}
+#endif
+#pragma float_control(precise, on)
+
+#pragma STDC FENV_ACCESS OFF
+
+#pragma STDC FENV_ROUND FE_DOWNWARD
Index: clang/lib/Parse/ParsePragma.cpp
===
--- clang/lib/Parse/ParsePragma.cpp
+++ clang/lib/Parse/ParsePragma.cpp
@@ -103,6 +103,11 @@
 
   void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer,
 Token &Tok) override {
+if (!PP.getTargetInfo().hasStrictFP() && !PP.getLangOpts().ExpStrictFP) {
+  PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+  << "FENV_ACCESS";
+  return;
+}
 tok::OnOffSwitch OOS;
 if (PP.LexOnOffSwitch(OOS))
  return;
@@ -2553,6 +2558,11 @@
  Token &Tok) {
   Sema::PragmaMsStackAction Action = Sema::PSK_Set;
   SourceLocation FloatControlLoc = Tok.getLocation();
+  if (!PP.getTargetInfo().hasStrictFP() && !PP.getLangOpts().ExpStrictFP) {
+PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+<< "float_control";
+return;
+  }
   PP.Lex(Tok);
   if (Tok.isNot(tok::l_paren)) {
 PP.Diag(FloatControlLoc, diag::err_expected) << tok::l_paren;
@@ -2952,6 +2962,11 @@
 Token &Tok) {
   Token PragmaName = Tok;
   SmallVector TokenList;
+  if (!PP.getTargetInfo().hasStrictFP() && !PP.getLangOpts().ExpStrictFP) {
+PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+<< PragmaName.getIdentifierInfo()->getName();
+return;
+  }
 
   PP.Lex(Tok);
   if (Tok.isNot(tok::identifier)) {
Index: clang/include/clang/Basic/DiagnosticParseKinds.td
===
--- clang/include/clang/Basic/DiagnosticParseKinds.td
+++ clang/include/clang/Basic/DiagnosticParseKinds.td
@@ -1147,6 +1147,9 @@
 def warn_stdc_unknown_rounding_mode : Warning<
   "invalid or unsupported rounding mode in '#pragma STDC FENV_ROUND' - 
ignored">,
   InGroup;
+def warn_pragma_fp_ignored : Warning<
+  "'#pragma %0' is not supported on this target - ignored">,
+  InGroup;
 // - #pragma comment
 def err_pragma_comment_malformed : Error<
   "pragma comment requires parenthesized identifier and optional string">;


Index: clang/test/Parser/pragma-fp-warn.c
===
--- /dev/null
+++ clang/test/Parser/pragma-fp-warn.c
@@ -0,0 +1,19 @@
+
+// RUN: %clang_cc1 -triple wasm32 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple thumbv7 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple aarch64 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple x86_64 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple systemz -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple powerpc -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+#ifdef EXPOK
+// expected-no-diagnostics
+#else
+// expected-warning@+8 {{'#pragma FENV_ROUND' is not supported on this target - ignored}}
+// expected-warning@+5 {{'#pragma FENV_ACCESS' is not supported on this target - ignored}}
+// expected-warning@+2 {{'#pragma float_control' is not supported on this target

[PATCH] D90316: [FPEnv] Diagnose pragmas FENV_ROUND,_ACCESS and float_control if target does not support StrictFP

[Kevin P. Neal via Phabricator via cfe-commits]

kpn added a comment.

I also added "-fexperimental-strict-floating-point" which makes it possible to 
write tests for a target when bringing up the support on that target. I think 
it would be confusing for that flag to work on command line arguments but not 
pragmas.


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[PATCH] D90316: [FPEnv] Diagnose pragmas FENV_ROUND,_ACCESS and float_control if target does not support StrictFP

[Melanie Blower via Phabricator via cfe-commits]

mibintc created this revision.
mibintc added reviewers: kpn, sepavloff, aaron.ballman, pengfei.
Herald added a project: clang.
mibintc requested review of this revision.
Herald added a subscriber: aheejin.

If the target doesn't support setting StrictFP, then ignore pragmas that modify 
the settings for rounding mode and exception behavior and FENV_ACCESS.
This was requested by @kpn see https://bugs.llvm.org/show_bug.cgi?id=47536
Also @pengfei suggested it as a solution for 
https://bugs.llvm.org/show_bug.cgi?id=47990


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Files:
  clang/include/clang/Basic/DiagnosticParseKinds.td
  clang/lib/Parse/ParsePragma.cpp
  clang/test/Parser/pragma-fp-warn.c


Index: clang/test/Parser/pragma-fp-warn.c
===
--- /dev/null
+++ clang/test/Parser/pragma-fp-warn.c
@@ -0,0 +1,19 @@
+
+// RUN: %clang_cc1 -triple wasm32 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple thumbv7 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple aarch64 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple x86_64 -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple systemz -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple powerpc -fsyntax-only -Wno-unknown-pragmas 
-Wignored-pragmas -verify %s
+#ifdef EXPOK
+// expected-no-diagnostics
+#else
+// expected-warning@+8 {{'#pragma FENV_ROUND' is not supported on this target 
- ignored}}
+// expected-warning@+5 {{'#pragma FENV_ACCESS' is not supported on this target 
- ignored}}
+// expected-warning@+2 {{'#pragma float_control' is not supported on this 
target - ignored}}
+#endif
+#pragma float_control(precise, on)
+
+#pragma STDC FENV_ACCESS OFF
+
+#pragma STDC FENV_ROUND FE_DOWNWARD
Index: clang/lib/Parse/ParsePragma.cpp
===
--- clang/lib/Parse/ParsePragma.cpp
+++ clang/lib/Parse/ParsePragma.cpp
@@ -103,6 +103,11 @@
 
   void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer,
 Token &Tok) override {
+if (!PP.getTargetInfo().hasStrictFP()) {
+  PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+  << "FENV_ACCESS";
+  return;
+}
 tok::OnOffSwitch OOS;
 if (PP.LexOnOffSwitch(OOS))
  return;
@@ -2553,6 +2558,11 @@
  Token &Tok) {
   Sema::PragmaMsStackAction Action = Sema::PSK_Set;
   SourceLocation FloatControlLoc = Tok.getLocation();
+  if (!PP.getTargetInfo().hasStrictFP()) {
+PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+<< "float_control";
+return;
+  }
   PP.Lex(Tok);
   if (Tok.isNot(tok::l_paren)) {
 PP.Diag(FloatControlLoc, diag::err_expected) << tok::l_paren;
@@ -2952,6 +2962,11 @@
 Token &Tok) {
   Token PragmaName = Tok;
   SmallVector TokenList;
+  if (!PP.getTargetInfo().hasStrictFP()) {
+PP.Diag(Tok.getLocation(), diag::warn_pragma_fp_ignored)
+<< PragmaName.getIdentifierInfo()->getName();
+return;
+  }
 
   PP.Lex(Tok);
   if (Tok.isNot(tok::identifier)) {
Index: clang/include/clang/Basic/DiagnosticParseKinds.td
===
--- clang/include/clang/Basic/DiagnosticParseKinds.td
+++ clang/include/clang/Basic/DiagnosticParseKinds.td
@@ -1147,6 +1147,9 @@
 def warn_stdc_unknown_rounding_mode : Warning<
   "invalid or unsupported rounding mode in '#pragma STDC FENV_ROUND' - 
ignored">,
   InGroup;
+def warn_pragma_fp_ignored : Warning<
+  "'#pragma %0' is not supported on this target - ignored">,
+  InGroup;
 // - #pragma comment
 def err_pragma_comment_malformed : Error<
   "pragma comment requires parenthesized identifier and optional string">;


Index: clang/test/Parser/pragma-fp-warn.c
===
--- /dev/null
+++ clang/test/Parser/pragma-fp-warn.c
@@ -0,0 +1,19 @@
+
+// RUN: %clang_cc1 -triple wasm32 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple thumbv7 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -triple aarch64 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple x86_64 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple systemz -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple powerpc -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+#ifdef EXPOK
+// expected-no-diagnostics
+#else
+// expected-warning@+8 {{'#pragma FENV_ROUND' is not supported on this target - ignored}}
+// expected-warning@+5 {{'#pragm