Add support for specifiying a language standard to bmake #234
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* docs/templates/bmake.txt:
* templates/bmake.mpd:
WalkthroughAdds a new templated variable languagestandard to the bmake documentation and hooks it into the build template so CCFLAGS can include -std= when defined. Changes
Estimated code review effort🎯 2 (Simple) | ⏱️ ~7 minutes Poem
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Actionable comments posted: 1
🧹 Nitpick comments (1)
docs/templates/bmake.txt (1)
22-22: Clarify scope (C++-only) and compiler support in the description of languagestandardMake it explicit this affects C++ compilation and only when the compiler understands -std=… to avoid confusion across compilers.
Proposed tweak:
-languagestandard = Which version of ISO C++ standard to compile against (c++14, c++17, c++20, c++23) +languagestandard = C++ language standard to compile against (e.g., c++14, c++17, c++20, c++23). Applied only when the selected compiler supports -std=...Also, please confirm whether this template is ever used with compilers that do not support -std= (e.g., non-GNU/Clang style), so we can consider adding a compiler-conditional guard if needed.
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📒 Files selected for processing (2)
docs/templates/bmake.txt(1 hunks)templates/bmake.mpd(1 hunks)
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- GitHub Check: VS2022Debug64
- GitHub Check: VS2022Release32
- GitHub Check: windows-2022 vs2022
- GitHub Check: macos-14-C++17
- GitHub Check: macos-13-C++17
- GitHub Check: ubuntu-24.04 g++-10
| RC = <%rc%> | ||
| LIBFLAGS = <%libflags%> | ||
| CCFLAGS = $(CC_CFLAGS)<%if(type_is_binary)%> $(BINARY_FLAGS)<%endif%><%if(compile_flags)%> <%compile_flags%><%endif%> | ||
| CCFLAGS = $(CC_CFLAGS)<%if(type_is_binary)%> $(BINARY_FLAGS)<%endif%><%if(compile_flags)%> <%compile_flags%><%endif%><%if(languagestandard)%> -std=<%languagestandard%><%endif%> |
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💡 Verification agent
🧩 Analysis chain
Do not append -std=… to CCFLAGS; it will be applied to C sources too and can break C builds
CCFLAGS is used for both C and C++ compilation rules in this template (.c, .cc, .cxx, .cpp, .C). Adding a C++ -std flag here will propagate to .c compilations, which Clang/GCC will reject (e.g., “invalid argument '-std=c++17' not allowed with 'C'”). This is a latent build break for projects containing C sources.
Minimal fix within this line:
-CCFLAGS = $(CC_CFLAGS)<%if(type_is_binary)%> $(BINARY_FLAGS)<%endif%><%if(compile_flags)%> <%compile_flags%><%endif%><%if(languagestandard)%> -std=<%languagestandard%><%endif%>
+CCFLAGS = $(CC_CFLAGS)<%if(type_is_binary)%> $(BINARY_FLAGS)<%endif%><%if(compile_flags)%> <%compile_flags%><%endif%>Follow-up (outside this hunk): introduce a separate flag used only by C++ rules and inject it into C++-only compile patterns (.cpp/.cxx/.cc/.C), not .c. Example:
Make variable definition near CCFLAGS:
CXX_STD_FLAG =<%if(languagestandard)%> -std=<%languagestandard%><%endif%>
Update compile commands for C++ sources by adding
- Parallel .cpp rule (Line 333):
From:
$(CC) ... $ (CCFLAGS) $(CFLAGS) ...
To:
$(CC) ... $ (CCFLAGS)$(CXX_STD_FLAG) $ (CFLAGS) ... - .cpp/.cxx/.cc/.C rules (Lines 338, 343, 347, 351):
From:
$(CC) ... $ (CCFLAGS) $(CFLAGS) ...
To:
$(CC) ... $ (CCFLAGS)$(CXX_STD_FLAG) $ (CFLAGS) ... - Per-file rule with transdir/buildflags (Line 361):
From:
$(CC) ... $ (CCFLAGS) $(CFLAGS) ...
To:
$(CC) ... $ (CCFLAGS)$(CXX_STD_FLAG) $ (CFLAGS) ...
Please confirm whether projects using this template include any .c sources. If they never do, we can keep the current approach; otherwise, the refactor above avoids C builds failing when languagestandard is set.
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#!/bin/bash
set -euo pipefail
echo "=== Show templates/bmake.mpd (first 220 lines) with numbers ==="
if [ -f templates/bmake.mpd ]; then
nl -ba templates/bmake.mpd | sed -n '1,220p'
else
echo "templates/bmake.mpd not found"
fi
echo
echo "=== Search for 'languagestandard' in repository ==="
rg "languagestandard" -n || true
echo
echo "=== Search for CCFLAGS definitions/usages across repo ==="
rg "CCFLAGS" -n || true
echo
echo "=== Show parts of templates/bmake.mpd around common compile rules (lines 300-420) ==="
if [ -f templates/bmake.mpd ]; then
nl -ba templates/bmake.mpd | sed -n '300,420p'
fiLength of output: 327
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#!/bin/bash
set -euo pipefail
FILE="templates/bmake.mpd"
echo "=== Show templates/bmake.mpd lines 1-220 ==="
if [ -f "$FILE" ]; then
awk 'NR>=1 && NR<=220{printf("%4d: %s\n", NR, $0)}' "$FILE"
else
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fi
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echo "=== Show templates/bmake.mpd lines 280-420 ==="
if [ -f "$FILE" ]; then
awk 'NR>=280 && NR<=420{printf("%4d: %s\n", NR, $0)}' "$FILE"
fi
echo
echo "=== Search for 'languagestandard' in repo ==="
if command -v rg >/dev/null 2>&1; then
rg -n "languagestandard" || true
else
grep -RIn "languagestandard" || true
fi
echo
echo "=== Search for CCFLAGS, CFLAGS, CXXFLAGS, and CXX occurrences in repo ==="
if command -v rg >/dev/null 2>&1; then
rg -n "CCFLAGS|CFLAGS|CXXFLAGS|CXX" || true
else
grep -RIn "CCFLAGS\|CFLAGS\|CXXFLAGS\|CXX" || true
fi
echo
echo "=== Show any lines mentioning -std= in the repo ==="
if command -v rg >/dev/null 2>&1; then
rg -n --hidden --no-ignore-vcs "\-std=" || true
else
grep -RIn --binary-files=without-match "\-std=" || true
fiLength of output: 23905
Do not put -std= into CCFLAGS — it will be passed to C compilations and can break C builds
Short reason: templates/bmake.mpd currently places -std=<%languagestandard%> inside CCFLAGS (confirmed at templates/bmake.mpd:100). CCFLAGS is used by the .c rule and per-file rules (see templates/bmake.mpd:353–355, 357–362), so C compiler invocations will receive C++ -std flags and may fail.
Files/locations to change
- templates/bmake.mpd
- Line 100: remove the <%if(languagestandard)%> -std=... piece from CCFLAGS.
- Insert a C++-only variable right after CCFLAGS, e.g. CXX_STD_FLAG.
- Update all C++ compile rules to use
$(CXX_STD_FLAG): parallel .cpp rule (≈line 333), .cpp/.cxx/.cc/.C rules (≈338, 343, 347, 351), and the per-file rule block (≈357–362). For the per-file rules, add $ (CXX_STD_FLAG) only when the source file is C++ (use the template conditional that checks the source-file language or extension).
Minimal diffs (apply to templates/bmake.mpd)
-CCFLAGS = $(CC_CFLAGS)<%if(type_is_binary)%> $(BINARY_FLAGS)<%endif%><%if(compile_flags)%> <%compile_flags%><%endif%><%if(languagestandard)%> -std=<%languagestandard%><%endif%>
+CCFLAGS = $(CC_CFLAGS)<%if(type_is_binary)%> $(BINARY_FLAGS)<%endif%><%if(compile_flags)%> <%compile_flags%><%endif%>
+# C++-only standard flag
+CXX_STD_FLAG =<%if(languagestandard)%> -std=<%languagestandard%><%endif%>Example compile-rule change (repeat for .cpp/.cxx/.cc/.C and parallel .cpp rules):
- $(CC) ... $(CCFLAGS) $(CFLAGS) $(WARN_FLAGS) -c ...
+ $(CC) ... $(CCFLAGS) $(CXX_STD_FLAG) $(CFLAGS) $(WARN_FLAGS) -c ...For per-file rules generated for each source file, conditionally add $(CXX_STD_FLAG) only when that source file is C++:
... $(CCFLAGS) <%if(source-file-is-cxx)%> $(CXX_STD_FLAG)<%endif%> $(CFLAGS) ...
Please confirm whether projects using this template contain any .c sources; if they do, apply the fix above. If none contain C sources, leaving the current template is harmless but fragile if a .c is later added.
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| CCFLAGS = $(CC_CFLAGS)<%if(type_is_binary)%> $(BINARY_FLAGS)<%endif%><%if(compile_flags)%> <%compile_flags%><%endif%><%if(languagestandard)%> -std=<%languagestandard%><%endif%> | |
| CCFLAGS = $(CC_CFLAGS)<%if(type_is_binary)%> $(BINARY_FLAGS)<%endif%><%if(compile_flags)%> <%compile_flags%><%endif%> | |
| # C++-only standard flag | |
| CXX_STD_FLAG =<%if(languagestandard)%> -std=<%languagestandard%><%endif%> |
🤖 Prompt for AI Agents
In templates/bmake.mpd around line 100, remove the <%if(languagestandard)%>
-std=<%languagestandard%><%endif%> piece from CCFLAGS so -std= is not passed to
C compilations; immediately after CCFLAGS add a new variable (e.g. CXX_STD_FLAG)
that expands to <%if(languagestandard)%> -std=<%languagestandard%><%endif%>;
update all C++ compile rules to use $(CXX_STD_FLAG) instead of relying on
CCFLAGS — specifically the parallel .cpp rule (~line 333) and the
.cpp/.cxx/.cc/.C rules (~lines 338, 343, 347, 351) — and in the per-file rule
block (~lines 357–362) conditionally append $(CXX_STD_FLAG) only when the source
file is C++ using the template conditional for source-file language/extension;
finally, verify whether projects using this template contain any .c sources and
if so apply these changes, otherwise note that leaving -std in CCFLAGS would be
fragile if a .c file is later added.
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Actionable comments posted: 1
🧹 Nitpick comments (2)
templates/bmake.mpd (1)
100-100: Confirm intended precedence for -std: it currently overrides -std set via ccflags/compile_flagsPlacing languagestandard last means it wins when multiple -std flags are present. If you prefer user-specified compile_flags to take precedence, swap the order.
Apply this diff to let compile_flags override languagestandard:
-CCFLAGS = $(CC_CFLAGS)<%if(type_is_binary)%> $(BINARY_FLAGS)<%endif%><%if(compile_flags)%> <%compile_flags%><%endif%><%if(languagestandard)%> -std=<%languagestandard%><%endif%> +CCFLAGS = $(CC_CFLAGS)<%if(type_is_binary)%> $(BINARY_FLAGS)<%endif%><%if(languagestandard)%> -std=<%languagestandard%><%endif%><%if(compile_flags)%> <%compile_flags%><%endif%>docs/templates/bmake.txt (1)
22-22: Tighten wording and punctuation; clarify C++-only intentMinor grammar fix and explicit note that it pertains to C++ sources. Also adds terminal punctuation for consistency.
-languagestandard = Which version of ISO C++ standard to compile against (c++14, c++17, c++20, c++23) +languagestandard = Specify the ISO C++ standard for C++ sources (e.g., c++14, c++17, c++20, c++23).
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📒 Files selected for processing (2)
docs/templates/bmake.txt(1 hunks)templates/bmake.mpd(1 hunks)
🧰 Additional context used
🪛 LanguageTool
docs/templates/bmake.txt
[grammar] ~22-~22: There might be a mistake here.
Context: ...table. languagestandard = Which version of ISO C++ standard to compile against (c+...
(QB_NEW_EN)
[grammar] ~22-~22: There might be a mistake here.
Context: ...ile against (c++14, c++17, c++20, c++23) libflags = Flags that are required to cr...
(QB_NEW_EN)
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- GitHub Check: Codacy Static Code Analysis
- GitHub Check: VS2022Debug64
- GitHub Check: VS2022Release32
- GitHub Check: macos-14-C++17
- GitHub Check: macos-13-C++17
- GitHub Check: ubuntu-24.04 g++-10
| CCFLAGS = $(CC_CFLAGS)<%if(type_is_binary)%> $(BINARY_FLAGS)<%endif%><%if(compile_flags)%> <%compile_flags%><%endif%><%if(languagestandard)%> -std=<%languagestandard%><%endif%> | ||
|
|
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💡 Verification agent
🧩 Analysis chain
C++ standard flag may be applied to .c compilations — verify this is acceptable or scope to C++ rules only
CCFLAGS is used by all compile rules, including .c. Appending -std=c++NN here may (a) be rejected by some compilers for C files, or (b) flip .c files into C++ mode. This can silently change semantics or fail builds in mixed C/C++ projects.
- If all supported Borland/Embarcadero compilers used via this template accept -std=c++NN on .c inputs (or always compile as C++), then OK.
- Otherwise, consider moving the -std=<%languagestandard%> addition into only the C++ pattern rules (.cpp/.cxx/.cc/.C) instead of CCFLAGS.
I can provide a follow-up patch that scopes the flag to C++-only rules if you confirm this is needed.
🏁 Script executed:
#!/bin/bash
set -euo pipefail
echo "Repository root: $(pwd)"
echo
echo "1) Show templates/bmake.mpd (first 400 lines):"
echo "------------------------------------------------"
if [ -f "templates/bmake.mpd" ]; then
sed -n '1,400p' templates/bmake.mpd || true
else
echo "templates/bmake.mpd not found"
fi
echo
echo "2) Search for CCFLAGS, -std and compile rule patterns:"
echo "------------------------------------------------"
rg -n --hidden -S 'CCFLAGS|\-std=|languagestandard|%.o: %.c|%.o: %.cpp|%.o: %.cxx|%.o: %.cc|\.c:|\.cpp:|\.cxx:|\.cc:' || true
echo
echo "3) Show lines around occurrences of CCFLAGS:"
echo "------------------------------------------------"
rg -n --hidden -S -n 'CCFLAGS' -n --line-number -n -H -S || true
echo
echo "4) Grep for common compile command usages (CC, CXX, CFLAGS, CXXFLAGS):"
echo "------------------------------------------------"
rg -n --hidden -S '\$\(CC\)|\$\(CXX\)|CFLAGS|CXXFLAGS' || trueLength of output: 27004
Scope -std=<%languagestandard%> to C++ compile rules in templates/bmake.mpd
Verified: CCFLAGS contains -std=<%languagestandard%> and that CCFLAGS is used by all compile rules (including .c), so a C++ standard flag will be passed to C compilations.
Files/locations to fix
- templates/bmake.mpd:100 — CCFLAGS includes
<%if(languagestandard)%> -std=<%languagestandard%><%endif%> - templates/bmake.mpd:333–361 — .cpp/.cxx/.cc/.C/.c compile rules all use
$(CCFLAGS)(so the -std flag will reach .c compilations)
Suggested change (minimal)
- Remove the languagestandard bit from CCFLAGS and add it only to C++ rules (or introduce a new CPP-specific var):
Original:
CCFLAGS = $(CC_CFLAGS)...<%if(languagestandard)%> -std=<%languagestandard%><%endif%>
Change to:
CCFLAGS = $(CC_CFLAGS)... # no -std here
And in the C++ rules (example non-parallel .cpp rule) append the flag:
.cpp$(OBJ_EXT):
$(CC) ... $(CCFLAGS) $(CFLAGS) <%if(languagestandard)%> -std=<%languagestandard%><%endif%> $(WARN_FLAGS) -c -o $(@D)\$(@F) $<
If you want, I can prepare a PR that moves the -std into the C++ rules (or introduces a CPP_STD_FLAGS variable and uses it only for the C++ patterns).
🤖 Prompt for AI Agents
In templates/bmake.mpd around lines 100 and 333–361, CCFLAGS currently contains
the C++ standard flag which gets applied to C compilations; remove the
<%if(languagestandard)%> -std=<%languagestandard%><%endif%> fragment from
CCFLAGS and instead add the standard flag only to C++ compile rules by either
(A) introducing a new CPP_STD_FLAGS (or CPPFLAGS/CPP_CFLAGS) conditional var
that expands to <%if(languagestandard)%> -std=<%languagestandard%><%endif%> and
appending that var to all .cpp/.cxx/.cc/.C pattern rules, or (B) directly
appending the existing <%if(languagestandard)%>
-std=<%languagestandard%><%endif%> to each C++ pattern recipe; ensure C pattern
rules keep using only CCFLAGS so they do not receive the C++ -std flag.
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